Description: (Applicant's Description) Specific Aims: 1. To perform safety and toxicity studies of MGH-1, MGH-2 vectors in Aoutus trivergedes. These studies will be performed using vectors produced in Project 1 (Chiocca), will involve the facilities of the New England Regional Primate Research Center; and provide tissues for CTL studies of Project 2 (Aim 3-Johnson) and neuropathologic studies Core C (Louis). 2. To implement human gene-marking and phase I studies by providing study design, documentation, and applications to IRB, GCRC and FDA for approval. To perform (in collaboration with Project 1) human gene-marking and phase I studies of MGH-1 vector (in year Y1,2), MGH-2 (Year 3, 4) and herpes vectors expressing transgenes for multiple drug activation in Y5. This aim will involve the coordination of the manufacture or GMP grade MGH-1, MGH-2 and other vectors by Dr. Richard Mulligan. Following acceptance of protocols by IRB and RAC, this Aim will implement clinical phase 1 and gene-marking studies. Funding is not requested for human studies nor for vector manufacture.